柱前衍生化HPLC用于顺铂纳米粒大鼠药动学的研究

目的建立一种改良的柱前衍生化-高效液相色谱法(HPLC)测定顺铂纳米粒大鼠血浆药物浓度,并将其应用于大鼠体内药动学研究。方法采用衍生化试剂二乙基二硫代氨基甲酸钠(DDTC)与顺铂络合生成Pt(DDTC)2衍生化产物,加入内标物地西泮,氯仿提取,挥干,乙酸乙酯复溶,采用HPLC法测定。色谱条件:色谱柱为C18,流动相为水-甲醇(体积比为1∶3),检测波长为252 nm。大鼠以7.5 mg·kg-1剂量分别尾静脉注射顺铂纳米粒和注射剂,不同时间取血,采用所建立的分析方法测定血浆顺铂质量浓度,计算药动学参数。结果本法可精密准确地测定顺铂纳米粒静脉注射给药后大鼠血浆中的顺铂质量浓度,线性范围为0.488~97.6 mg·L~(-1),最低定量限为100μg·L~(-1),日内、日间变异系数均<5%。顺铂纳米粒的主要药动学参数:ρmax为(62.85±13.83)mg·L~(-1),t1/2为(3.53±1.57)min,AUC0-∞为(176.81±46.19)mg·L~(-1)·h,CL为(44.89±11.91)m L·kg·h-1。结论该方法适用于顺铂纳米粒体内药物质量浓度测定及其药动学的研究。与顺铂注射液相比,顺铂纳米粒药时曲线下面积显著提高,清除率显著降低,其药动学的改变有利于降低药物的毒副作用。     

Pharmacokinetic study of ilexgenin A in rats

目的 探讨静脉给予ilexgenin A后大鼠体内的药物动力学特征.方法 采用HPLC测定大鼠血浆中的血药浓度,用DAS 2.0药动学软件求算其药动学参数.结果 Ilexgenin A在大鼠体内呈二室模型分布,主要药动学参数为:t1/2α=0.545min,t1/2β=18.338 min,Cl =0.019 L·min-1·kg-1,AUC0→1=2.5902 g·min·L-1.结论 所用方法可用于大鼠血浆中ilexgenin A的检测及其体内药动学研究;静脉给药后,ilexgenin A在大鼠体内分布和消除迅速.     

泮托拉唑钠在大鼠体内药动学研究

目的建立HPLC法测定大鼠血浆中泮托拉唑钠对映体,研究泮托拉唑钠在大鼠体内药动学特征。方法血浆用醋酸乙酯提取,以非那西丁为内标,Chiralcel OJ-RH色谱柱(250 mm×4.6 mm,5μm),流动相为20 mmol/L磷酸二氢钠(含0.01%磷酸)–乙腈(78∶22),紫外检测波长为288 nm,体积流量为1.0 m L/min,柱温40℃。大鼠尾iv消旋体16 mg/kg,HPLC-UV法测定血浆中左旋和右旋泮托拉唑钠浓度,并采用DAS 2.0软件计算药动学参数。结果左旋泮托拉唑钠、右旋泮托拉唑钠线性范围均为0.156~40.000μg/m L,定量限为0.156μg/m L。泮托拉唑钠左旋体与右旋体的主要药动学参数分别为:Cmax(38.13±3.33)、(40.52±3.69)μg/L;AUC0-τ(1 688.45±302.38)、(1 399.88±376.44)min·μg/m L;AUC0-∞(1710.61±309.40)、(1 417.29±383.21)min·μg/m L;t1/2(30.92±6.41)、(22.37±7.59)h。结论泮托拉唑钠对映体在大鼠体内的药动学存在立体选择性特征,为临床合理应用手性药物泮托拉唑钠提供参考。     

毛冬青皂苷元ilexgenin A在大鼠体内的药动学研究

目的探讨静脉给予ilexgenin A后大鼠体内的药物动力学特征。方法采用HPLC测定大鼠血浆中的血药浓度,用DAS 2.0药动学软件求算其药动学参数。结果 Ilexgenin A在大鼠体内呈二室模型分布,主要药动学参数为:t1/2α=0.545min,t1/2β=18.338 min,Cl=0.019 L·min-1.kg-1,AUC0→t=2.5902 g·min·L-1。结论所用方法可用于大鼠血浆中ilexgeninA的检测及其体内药动学研究;静脉给药后,ilexgenin A在大鼠体内分布和消除迅速。     

姜黄素固体脂质纳米粒在大鼠体内的药动学

目的:研究姜黄素固体脂质纳米粒在SD大鼠体内的口服药动学情况。方法:大鼠单剂量灌胃给予姜黄素固体脂质纳米粒和游离药姜黄素,眼底静脉丛取血,以醋酸乙酯处理血浆样品,尼群地平为内标,高效液相法(HPLC)测定血浆中姜黄素的含量,并用药物与统计(Drug and Statistics,DAS)软件分析处理药动学数据。结果:姜黄素固体脂质纳米粒和游离药姜黄素在大鼠体内的药动学行为均符合二室开放模型,姜黄素固体脂质纳米粒和游离药姜黄素的药动学参数分别如下:药时曲线下面积(AUC0-t)为(798.00±64.44)μg·h·L-1和(108.78±14.22)μg·h·L-1,药时曲线下总面积(AUC0-∞)为(939.49±114.18)μg·h·L-1和(126.99±28.14)μg·h·L-1,峰浓度(Cmax)为(93.84±5.66)μg·L-1和(72.46±2.66)μg·L-1,消除半衰期(t1/2)为(17.16±1.61)h和(4.71±1.18)h,姜黄素固体脂质纳米粒的AUC0-t、AUC0-∞、Cmax和t1/2分别提高了7.34,7.40,1.30和3.64倍。结论:姜黄素固体脂质纳米粒体内消除慢,血药浓度高,且明显提高了姜黄素的口服生物利用度。     

鸡屎藤次苷在大鼠体内的药动学研究

目的:测定大鼠血浆中鸡屎藤次苷的含量,并研究其在大鼠体内的药动学过程.方法:采用HPLC -UV法测定大鼠尾静脉注射给药后血浆中鸡屎藤次苷的血药浓度.色谱条件为:DiamonsilTM C18柱(250 mm×4.6 mm,5μm),流动相:甲醇一乙腈-0.1％冰醋酸(3:2:95,v/v/v),流速:1.0 mL·min-1,检测波长:230 nm.通过BAPP2.0软件求算其药动学参数.结果:鸡屎藤次苷血浆浓度在0.2～40μg·mL-1(Y=0.07321X-0.00939,γ=0.9940)范围内线性关系良好.日内精密度不大于7.1％,日间精密度不大于13.5％,准确度RE值在一4.5％～1.8％之间.鸡屎藤次苷提取回收率为64.5％～73.1％,内标物提取回收率为74.5％.主要药动学参数为t1/2=(33.5+4.39) min,AUC0-180mm=(922±129) μg·min· mL-1.结论:该法专属、准确、灵敏,适用于鸡屎藤次苷在大鼠体内的药动学研究,为进一步研究鸡屎藤次苷体内药动学行为提供了依据.     

大鼠血浆中山奈酚的HPLC测定法及其在药物动力学研究中的应用

目的建立测定大鼠血浆中山奈酚质量浓度的HPLC法,并用于山奈酚经灌胃给药后在大鼠体内药动学研究。方法大鼠灌胃给予200 mg.kg-1山奈酚混悬液,于给药后不同时间采集血样,以非那西丁为内标,VC为抗氧剂,采用2 mol.L-1盐酸,80℃水浴水解30 min后用乙醚萃取的方法处理血浆样品。采用RP-HPLC法测定山奈酚血药质量浓度,色谱柱为Diamonsil C18柱(250 mm×4.6 mm,5μm),流动相为乙腈-体积分数为0.05%磷酸溶液(体积比40∶60),流速为1.0 mL.min-1,检测波长为370 nm,柱温为40℃。结果血浆中内源性物质对山奈酚测定无干扰,线性范围为0.050～10 mg.L-1,r=0.998 5,回收率、准确度及日内、日间精密度均符合生物样品测定要求,定量下限(LLOQ)为50μg.L-1。山奈酚主要药动学参数为AUC0-t=129.2 mg.h.L-1,ρmax=7.39mg.L-1,tmax=9.0 h,t1/2=8.3 h。结论该方法简便、快速、重复性好,适用于山奈酚大鼠血药质量浓度测定及体内药动学研究。     

HPLC法测定大鼠血浆中槐定碱

目的建立HPLC法测定大鼠血浆中槐定碱的体内分析方法,并用于其药动学研究。方法以苦参碱为内标,血浆样品在1.0mol·L-1氢氧化钠碱性条件下加入1.0mL三氯甲烷液-液萃取,采用Synergi 4μHydro-RP 80A(150mm×4.6mm,4.0μm)色谱柱分离,流动相为乙腈-磷酸盐缓冲溶液(0.01mol·L-1 KH2PO4,磷酸调pH 3.00)=5∶95,流速为1.0mL·min-1,柱温30℃,检测波长210nm,在此条件下测定。采用DAS 2.0软件进行药动学参数估算。结果槐定碱在0.25~25μg·mL-1内线性良好(r=0.999 7),提取回收率为76.6%~90.4%,日内、日间精密度符合要求。槐定碱主要药动学参数t1/2、AUC、Cmax分别为1.75±0.66h、10.80±2.69mg·h·L-1和5.56±0.78mg·L-1。结论该方法快速、灵敏、专属性强,可用于槐定碱药的代动力学分析。     

HPLC法测定人血浆中奥美拉唑浓度

目的建立人血浆中奥美拉唑的HPLC测定方法,并对奥美拉唑在健康志愿者体内进行药动学研究。方法采用内标法,以乙醚进行提取,提取液吹干,残渣用甲醇溶解后进行HPLC法检测;色谱柱为DiamonsilC18(150mm×4.6mm,5μm),流动相为甲醇-乙酸胺缓冲液(58∶42,V/V),其中缓冲液组成为水-醋酸-三乙胺(98∶1∶1,V/V),流速1.0mL·min-1,检测波长302nm。测定了24名健康志愿者单剂量口服40mg奥美拉唑胶囊后不同时刻奥美拉唑血药浓度,并采用DAS软件对其体内药动学参数进行估算。结果本测定方法的方法回收率为98.34%~105.87%,线性范围为10~2000μg·L-1。24名健康志愿者体内药动学采用统计矩分析,tmax为(2.11±0.73)h,t1/2为(1.03±0.56)h,ρmax为(776.30±341.55)μg·L-1,MRT0→t为(3.04±0.80)h,AUC0→12为(1749.90±1241.73)μg·h·L-1,AUC0→∞为(1790.48±1309.45)μg·h·L-1。结论本方法灵敏度高,重现性好,专属性强,适合临床药动学研究。     

大鼠血浆中野黄芩苷的HPLC测定及其药动学研究

建立了HPLC法测定中药复方茵山莲颗粒灌胃后大鼠血浆中野黄芩苷的浓度,并研究了其在大鼠体内的药动学。以黄芩苷为内标,采用C18柱,乙腈-四氢呋喃-0.4%磷酸(15∶35∶150)为流动相,检测波长为335nm。野黄芩苷浓度在0.025～0.16μg/ml范围内线性关系良好(r=0.9946),定量限为0.025μg/ml,日内和日间RSD均小于10%。主要药动学参数为cmax(0.765±0.158)μg/ml,tmax(3.67±0.47)h,t1/2(10.78±2.63)h,AUC0-36(7.66±1.63)μg·h·ml-1,AUC0-∞(8.46±1.79)μg·h·ml-1。     

Efficacy of gut lavage,hemodialysis, and hemoperfusion in the therapy of paraquat or diquat intoxication

Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.

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Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.

     

In vitro studies on sterically stabilized liposomes (SL) as enzyme carriers in organophosphorus (OP) antagonism

This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine.     

Aquatic Insects and Trace Metals: Bioavailability,Bioaccumulation, and Toxicity

Abstract

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.     

Pharmacological treatment of COVID-19: an opinion paper

The precocity and efficacy of the vaccines developed so far against COVID-19 has been the most significant and saving advance against the pandemic. The development of vaccines has not prevented, during the whole period of the pandemic, the constant search for therapeutic medicines, both among existing drugs with different indications and in the development of new drugs. The Scientific Committee of the COVID-19 of the Illustrious College of Physicians of Madrid wanted to offer an early, simplified and critical approach to these new drugs, to new developments in immunotherapy and to what has been learned from the immune response modulators already known and which have proven effective against the virus, in order to help understand the current situation.     

Alzheimer’s disease – current trends in basic and clinical research. Highlights from the 16th ECNP

Advances in the molecular biological knowledge of neuronal nicotinic acetylcholine receptors (nAChRs) have led to a growing interest by the pharmaceutical industry in the development of novel compounds that selectively modulate nAChR function. The ability of (-)-nicotine, an activator of nAChRs, to enhance attentional aspects of cognition in animals and humans, to exert neuroprotective and anxiolytic-like effects, and presumably to mediate the negative correlation between smoking and Alzheimer's (and Parkinson's) Disease, has focused interest on the potential therapeutic utility of modulators of nAChR function for treatment of some of the deficits associated with these progressive, neurodegenerative conditions. Numerous compounds are known which activate nAChRs and which might serve as lead compounds toward the development of such agents. The pharmacologic diversity of neuronal nAChR subtypes suggests the possibility of developing selective compounds which would have more favourable side-effect profiles than existing agents. This broader class of agents, collectively called cholinergic channel modulators (ChCMs), is anticipated to encompass compounds which would have more favourable side-effect profiles than existing agents, which generally exhibit low selectivity. This selectivity may be achieved by preferentially activating some subtypes of nAChRs (i.e., Cholinergic Channel Activators, ChCAs) or inhibiting the function of other subtypes (Cholinergic Channel Inhibitors, ChCIs). An overview of the biology of nAChRs and the rationale for the use of ChCMs for the treatment of dementia related to neurodegenerative diseases are presented, followed by a discussion of lead compounds and compounds under consideration for clinical evaluation.     

Steroidal sapogenin contents in some domestic plants

In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins.